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Supreme Court to Decide Standard for Proving Invalidity of a Patent

Today the U.S. Supreme Court agreed to hear Microsoft’s appeal in a case that could make it easier to invalidate a patent. If successful, Microsoft’s challenge should help in the fight against bad patents by leveling the playing field for showing that a patent is invalid. A Microsoft win in the case would benefit not only Microsoft, but also the free and open source software community. That’s why EFF, joined by Public Knowledge, the Computer & Communications Industry Association and the Apache Software Foundation, filed an amicus brief in the Supreme Court supporting Microsoft.

As we previously reported, here’s some background: In court, parties have to prove their case by some "standard of proof." In almost all civil cases, the standard is "preponderance of the evidence" – meaning it is more likely than not that the facts are true. When the question is invalidating a patent, however, the U.S. Court of Appeals for the Federal Circuit decided that a defendant trying to prove a patent invalid must do so by a higher standard than normal civil cases, that of "clear and convincing" evidence. "Clear and convincing" means that the facts are "highly probable," which is a much more difficult standard to meet than just a preponderance.

In a case three years ago, the Supreme Court had suggested that this high standard of proof should not apply where the prior art involved was not considered by the Patent Office before it issued the patent. Even still, the Federal Circuit has left the clear and convincing evidence standard untouched.

In today’s case, i4i Ltd. had sued Microsoft for patent infringement. i4i claimed its patent covered editing documents that contain markup languages like XML (Microsoft Word had XML editing capabilities). Microsoft had argued that i4i’s patent was invalid because the disclosed invention had been embodied in a software product sold in the United States more than a year before the patent application was filed – prior art that the patent examiner did not consider. The Federal Circuit applied its clear and convincing standard and rejected Microsoft’s invalidity argument. Microsoft petitioned the Supreme Court for certiorari, and was supported by eleven amicus briefs, including EFF’s. That Court has now granted Microsoft’s request to decide whether the Federal Circuit’s standard of proof rule is correct.

EFF argued in its brief that the Federal Circuit’s requirement that an accused infringer prove patent invalidity by "clear and convincing" evidence unfairly burdens patent defendants, especially in the free and open source software context. The standard undermines the traditional patent bargain between private patent owners and the public and threatens to impede innovation and the dissemination of knowledge. EFF is of course concerned with the effect illegitimate patents have on innovation.

We are pleased that the Supreme Court has agreed to hear Microsoft’s petition, and hope that this case will help to level the patent playing field. Now that the case will be fully briefed, EFF and its other amici will likely file another brief supporting Microsoft. A decision is expected by June 2011.